Electric-arc lamp.



F. w. GORE.

ELECTRIC ARC LAMP.

APPLICATION FILED JAN. 7, 1905.

1,142,248. Patented June 8, 1915.

a SHEETS-SHEET 1.7 9

L Mm I w 7/ IUVe roF. Fred- W. Gore.

F. W. GORE.

ELECTRIC ARC LAMP.

APPLICATION FILED JAN. 7, 1905.

Wfinesses.

lnven ror.

F ed W. Gore.

F. W. GORE.

ELECTRIC ARC LAMP.

APPLICATION FILED JAN-7,1905.

1 ,142,248, Patented J 11116 8, 1915.

a sums-sum a. 71

wi messes. inveni'on rrnn STATES PATENT OFFICE.

'FREDEEECFZI VJ. GORE, 0F QUINCY, MA$SACHUSETTS, ASSIGNOR QF QNE-FOUBTI-I T0 AND QNE-FOURTH T0 FRANK ttnrrr.

Application filed January 7, 1905.

To all whom, it concern Be it known that l, FnnonniorclWmLiAM Gone, a citizen or the United States, residing at Quincy, in the county of Norfolk and State of Massachusetts, have invented cernew and-useful improvements in Electrrc-Arg Lamps, of which the following is the separation of the carbons is effected by lifting away the upper carbon from the lower until the are is established, the lower carbon remalnlng in such raised position during the subsequent'operation of the lamp.

A decrease in the operative length of the carbons, owin to consumption thereof, is compensated or by a gradual feed of the upper carbon, but assuming that the clutch does not slip upon the upper carbon while current is flowing through the lamp, said upper carbon is not permitted to come into contact with the lower carbon during the normal period of service of the carbons,

whereby the flickering of the light is overcome and the arc is kept constant and practically unchanged so far as regards its luminosity and color.

The descent of the upper carbon is arrested, in the present invention, by the action oi a clutch which is under the control oi the starting coil or solenoid. A dash pot con trols the upward movement of the solenoid plunger before and after the clutch, becomes operative, and after the clutch becomes operative, then a retardation device checks or controls the tendency of a continued uplift of the upper carbon. The retardation device, in conjunction with the dash pot, counteracts, to a certain extent, the quick uplift of the upper carbon during the first onrush of the current. The weight of the up per carbon and its carrier is sustained by the clutch when the solenoid is energized, but

specification of Letters ."Eatent.

Patented June 8, i915,

No. canoes.

when the clutch is released from the upper carbon, the retardation device supports the upper carbon and controls the movement thereof. Thus, during the descent of the upper carbon, in the subsequent operation oi the lamp to feed said upper carbon, the retardation device supports substantially the weight of the upper carbon and the carrier therefor at such times when the clutch is released from gripping engagement with said carbon.

The retardation device for the upper carbon becomes efi'ective in controlling the descent tliereoi when the clutch is released, but this device is so constructed that the feed of the carbon is so slow and gradual as to be imperceptible to the eye. The clutch and the carbon controlling retardation device are so related that when the former is not gripping the carbon the latter is controlling its descent in such a gradual manner as to maintain the are practically uniform and steady, clear and bright at all times. Furthermore, this retardation device is so constructed that it will not be afiected by changes in temperature due to the heating eifect of the current or the cooling action of the air; and, furthermore, this device compensates for any changes in the position of the carbon carrier when manipulated by the attendant in replacing a burned carbon by a fresh one.

My invention embraces, also, a novel lifting device in connection with the lower carbon carrier, and a retardation device for said lower carrier, said retardation device being designed to check and control any sudden or quick movement of the lower carrier when free to move. Such devices are combined with means for-permitting their adjustment bodily in a lateral direction to allow the attendant to obtain access to the lower carrier for replacing the carbons therein. Further objects and advantages of the invention will appear in the course of the subjoined description, and the actual scope of the invention will be defined by the annexed claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, wherein like characters of reference are used to indicate corresponding parts in all the figures.

Figure 1 is an elevation, partly in section,

of an arc lamp constructed n accordance with my invention, 2 is an enlarged vertical sectional elevation through the devices at the lower part of the lamp. ig. 3 is a sectional plan view, in the plane indi cated by the dotted line 33 of 2, showing the foot plate of the lamp in its normal position by full lines, and in an adjusted position by dotted lines. t is a detail view in elevation, showing the locking device for the foot plate; Fig. 5 is another detail view in elevation, of the movable member of said locking device, shown by Fig. ti is a detached view of one embodiment of means for preventing the accidental removal of the checkingrnut at the lower extremity of the lamp. Fig. 7 is an enlarged view, partly in The general framework of the lamp con.

sists of a top plate Lafoot plate 2, intermediate plate 3, vertical rods 4, a canopy or top 5, and a suitable housing or casing for the working parts at the upper portion of the lamp, said housing or casing beinghere in shown as consisting of the members 6, I, and 8, although the detail construction oi the casing is not materlal and may be modified or changed at will. The hood :5, is at. tached to the top platel, in any usual or' preferred way, and the lamp is hung or suspended by means of a hanger 9, which may be connected to any suitable supporting device. The member 6 of the casing; is shown as being attached to the hood 5, and the member 7 is intermediate of the members 5 and 8, for the purpose of joining them one to the other, said intermediate member '3 of the casing being shown as having a flared lower portion 10, which is adapted to inclose the upper part of the usual lamp globe ill. The intermediate plate 3 of the lamp-frame is connected by the rods 4i to the foot plate 9, and said plate 3 is designed to be'connected rigidly with the top plate 1 by suitable rods, (not shown).

The upper and lower carbons, of the usual or any preferred type, are indicated at A, B, respectlvely, and with each carbon is associated a carbon holder and a retardation device, the retardation device for the lower carbon B acting indirectly thereon through a slidable frame. This slidable frame is herein shown as a pair of tubes 12, l3,and a plate 1d, the end portions-of said plate being provided with sleeves or bosses 15, which are titted on the lower end of the frame tubes l2, 13, so as to be movable therewith. The rods 4 of the lamp-frame are shown as tubular, and they extend through the tubes l2, 13, of

frame, so as to lire the same,

' lower carbon and the slidable frame.

the slidable frame, said tubular members of the frame being fitted loosely on the rods 4:, so as to be capableof a limited vertical movement thereon The movement of theslidable frame in an upward direction is secured by the expansive energy of coiled springs 16, two of which. are preferably employed, although the number is innruatr-irial. Said springs are housed. or incased within the lower end por tions of the tubular rods 4, and each spring" is seated on a plug or block 17, which is movable endwise in one tubular rod (see 2), each blocr l7 adjusted by a threaded stem 18, which is provided with an exposed lrnob l9, and is screwed into a female thread at the lower extremity of the tubularrod The upper part of each spring 16 acts on a plug 20, which is slidable in the tubular rod 4L, and to this plug isattached a pin 21', the latter extending loosely through a slot 22, provided in the rod 4-, said pin being secured in the sleeve 15 and to the lower portion of one tube 12, or 13, of the slidable frame. it will be seen that the springs 16 are adapted to exert pressure in an upward direction on the pins 21, and the tubular members l2, l3, of said slidable and the com-- pression or pressure of said springs 16 may be adjusted or regulated by turning the lrnobs l9 of the threaded stems l8.-

The plate it forming a part'of the slidable frame lies at a suitable distance above the foot plate 2 of the main lamp-frame, and this plate it carries the holder 23 for the lower carbon B and the holder 24, on which is seated the arc-in'closing globe 25. The

' lower carbon holder 23 and the globe holder being attached to the carbon holder 23' to surround or inclose it, and the holder 23 is clamped by suitable devices 27 to the plate it of the slidable frame, whereby the carbon holder 23 and the globe holder 2% are movable up and down with said slidable frame. The foot plate 2 is adjusted in ahorizontal plane by a swinging movement, and said foot plate carries the retardation device for tie S 1 herein shown, the foot plate 2 is provided at one end witha short sleeve 28-, said sleeve extending upwardly toward the plate ll of the slidable frame and fitting loosely on one tubular rod 4 of the lamp-frame, whereby the foot plate Q is pivotally connected with a member of the la Imp-frame for swinging adjustment on a vertical axis. The other end of this foot plate 2 is provided with a notch 29 (see Fig; 3), and when in normal position this notched end of the foot plate mesons ex is adapted to lit erounddhe other tubular rod i of the lernp-frame, as shown by Fig. 2, said free notched end of the foot plete being held in its normal position by any suitable type oi catch 30.

A short casing or housing 31, is secured firrnly to the middle part of the foot plate 2 in o, way to extend downwardly therefrom, and to the lower part of said casing is secured e transverse pin 32. Ageinst the lower open end of the casing 31 is fitted a holder 33 for lamp globe ll, seid globe being shown as having its lower fiene'ed en seated upon the holder 83. A sp ng is seated on the globe in order to hold it steadily in place, and this spring is adapted to be fastened on or connected with the casing ill in e suitsble way The holder 33 is clamped place against the lower end of i the seeing 31 by e not 35, which is threaded on a stem 36 (see Figs. 9 and 6), The stern has on eye 37, through which posses is pin 32' tl v letter operating to connect the threaded stem 36 with the casing 31 is evident that the not 35 may be screwed on tho 36 to firmly claim the holder 83, between the ca and pre- VBll) e n*" worlling loose accidenlocking 38, one end in a slot 39 provided L end the susp ded bolt 3, lower or the dog 38 is pvotelly UN. sons 1 ted by n 40 i1? "be lower posed .onloer lower dog is of the bolt 36 gravity inits shoulde to lie in the A out said dog nny be pressed inwdo; i

so as to lie within is bolt 36 thereby DGflilltlllH the not 35 to be on screwed from the stem.

lh-Je retardation device of the slideble frame and the lower carbon consists of piston heed 2, a cylinder 48, end on operetive connection between said cylinder end the cross plate 14 of the slideble ironic. lhe piston head 4% is anchored in e stationary position lower part of the lamp, while the cylinder i3 is adapted to travel with the "frame plate This piston head 42 may be constructed any suitable wey end of any epproprizite material, but I prefer to use e plug or" plumbago or graphite which is clamped by plates 4 to a stem 4:5 the latter being attached to the pin 32 fixed in the casing 31 whereby the piston head 42 is anchoreol in'place. The cylinder 43 of the re tardation device is open at its lower end while its upper end is closed by e head .26., the latter being provided with a boss 4?, and with an air inlet chamber 48. In the head i6 is a port 49, adapted to establish ting the i communication between the chamber of the cylinder 43 and the chamber 48, and in this last mentioned chamber is a check valve 50, which is adapted to be drawn by suction downwardly and tightly against a seat for the purpose of closing the port 49 on the upward movement of the slidable frame and the lower corloon whereby the retardation device operates to insure a slow steedy movement to the slideble frame when the current is admitted to the lamp, said frame having e steady progressive movement and free from 2i jerky or irregular travel. I

' The means for connecting the cylinder of the retardation device with the frame plate M provide a detachable connection between said retardation device and the slidable frame so "as to permit the r tcrdotion device to be adjusted with the foot plate 2; when the letter is swung in a horizontal path around the axis afforded by one of the to. bnler rods 4i of the lower carbon l der 23 is exposed to per rnit the introduction or removal the C211 bcns. A thiinble extends downwardly f om he frame p e i i said t l slot A rotatable hollow plug loosely the tliiinble 51 said plug havn s sin 54- erranged in the bayonet e ping is provided below the nee w el Co which is t nble 51 nor all,

venient edinstinc thn'nb wheel eing oe upper face of the foot pl the shenli: of which extends below the them wheel 55-, end is arranged to enter the sleeve ii, forming e part of the head 4:6 for the cv lClGl d3 of the lower retordetion device, said stem 56 being attached to the cylinder head 46 by a transverse pin or key 57. The parts 53 56, form the members of a ball and socket connection between the movable cylinder d3 of the retardation device, and the plate 1% oi the slideble irnmethus com pensoting for any irregularities in the position of the retardation device to the slideble frame.

it is evident that the rotative plug 53 may be turned for the pin 54. to lie infthe- 3 lamp-trance whereby Y ting ready access to be obtained to the can and the binding nuts 27, so that there is no bon holder 23, for inserting or removing the carbons A, B. ldor restoring the to their normal positions, the loot plate 2 is moved in an opposite direction so that its notched end 29 will lit around one of the tubular rods 4, said end of the foot plate being engaged by the catch 30. The slidable frame is now lowered for the thiinbl'e 51 to over the rotative plug 53, the pin said plug sliding into the vertical leg or? the bayonet slot 52, after which the plug is turned for the pin 54 to enter the horizontal arm of said slot, whereby the parts are connected .operatit elyso that the lower retardation device will control the upward movement elf the slidable frame and the carbon holder,

Within the thimble 51 is an insulating plug or washer 58, which fits tightly in the rotative plug '53, and is adapted to support the carbon should it drop accidentally, said plug 58 serving when the carbon is, through carelessness, dropped accidentally upon it, to insulate the carbon electrically from the retardation device at the lower part of the lamp. it

By reference to Fig. 2 it is to be noted that the lower carbon carrier 23 is insulated electrically from plate 14 by vertical screws, the latter being provided with thumb nuts 27. The screws pass through suitable apertures in parts 23, it, and'through insulating materials positioned between said parts 14, 23, and between these last named parts metallic connection between parts it and 23.

Iwill now proceed to describe the devices for feeding and controlling the movement of the upper carbon A, one of which'devices, hereinafter termed the clutch, is efi'ective normally in checking or arresting the downward movement of the carbon when the current flows through the lamp, while the other device, hereinafter termed theupper retardation mechanism, acts to automatically control the downward movement of said carbon when released from the first device, or clutch, such control of the upper carbon insuring an exceedingly slow and steady teed movement, but which is suficient to compensate for the consumption of the carbon by the burning of the arc.

The electrlcally actuated means for clutching the upper carbon A. are similar in many respects to some types of electrical lamps. The current is admitted at the positive bind ing post 59 and is conducted to and through a resistance coil 60, the latter enveloping an insulating drum 61, preferably of porcelain, and attached to the top plate lor the hood 5, in any suitable or preferred way, said resistance coil being contained withm the'part 6 of the housing. Supported withare.

in the 7', c" ing coils or sol legs of yoh this armatu rod tit (indi l), which that is to impinge on the upper carbon A. the clutch and the devices for checking or locking the upper carbon A, together with the magnet or solenoid 62, are ordinary in the art, so that I do not consider it necessary to particularly illustratev and describe thesame. *With the checking devices for the upper carbonis associated a dash-pot, the positionof which is indicated at 66, and which is adapted to hold in check the moveinent ofthe armature when the current is allowed to pass through the coils of the solenoid, in the absence of this dash- LlCl. housing are the startd 62, in which works the ed armature 63, and with sassociated a suitable, clutch ted by dotted lines in Fig.

pot a sudden rush of the current would M fore, that the dash-pot in the lamp operates as a check and provides an elastic resistance to the force developed bythe magnets As shown more particularly by Figs. 7 8

and 9, the retardation deviceconsists of an elongated tube 67, a piston head 68, and

means whereby a vacuum is established in the upper part of the tube 67.011 the descentof the piston head 68. Said tube 67 is suspended flexibly from the top plate 1 of the lamp-frame by a ball and socket connection therewith, and as shown, I employ a bolt 69 as the operative connection between the retardation tube and said top plater A boss '70 is provided on the top plate for the reception of an insulating plug orwasher 71, the latter being clamped to the top plate by a gland 72, which is screwedon the boss 70. The hanger bolt 69 passes through and is secured in the insulating washer il, so as to be electrically insulated from the metallic plate of the lamp-frame. The lower end portion of the hanger bolt 69 is formed With a rounded or globular head 73, which is fitted in a socket of a coupling memberld, the latter being externally threaded and screwed into a temale threaded chamber 75, which is provided in a head 76." Thishead is externally threaded and screwed into a female threaded up er end portion 77 of the retardation tube 6 and the head 76 is furthermore provided with a chamber 78 and a, port 79, said port establishing communica-I tion between'the chamber 78 and the piston chamber 67 of the tube 67. The bottom portion of the chamber 78 is-fashioneditoserve as a valve seat ada ted for the accom modation of aball or c eck valve 80, the latter being fitted loosely in the chamber 78, and intended to close the port 79 against the ingress of air on the downward movement.

u h rodcontrols the clutch'65,

retardation device.

of the piston head 68, thereby establishing a partial vacuum in the piston chamber 67 and insuring a very slow movement to the piston head and the carbon A, which is movable therewith.

l or regulating the efiective area of the port 79 and the inlet of air to the piston. chamber 67, l have provided another valve 81, which I will designate as a regulating valve to distinguish it from the automatic check valve 80. The sole function of the regulating valve 81 is to vary the area of the port 79 in head to seas to regulate the flow of air through the port when the piston head 68 is reciprocated in the tube 67 of the This regulating valve has a tapering iace adaptedto be adjusted quite close to or in contact with a valve seat, which is provided at the lower eutrern ity of the port 79, and said regulating valve is carried by a bridge plate 82 the latter being in one piece with a plate or Washer 83, that is screwed into the upper threaded part oi the retardation tube 67. Said washer $8 lies below and is independent of the head or closure Y6 for the retardation tube, and said closure 76 together with the Washer 83 may be screwed into the retardation tube so that the parts 76, 83, have such relation one to the other, that the valve 81 will provide an air passage of the proper area to permit the flow of air in the desired volume.

The current admitted to the resistance coil 60 flows through the magnet 69;, and is supplied to the carbon by means or" conductors 8t, 85. The conductor 84% leads fromone of the coils of the magnet 62 and is attached to theretardation tube 67, below the Washer 83, which carries the regulating valve 8L the connection being made through an insulated bushing 86. The conductor 85 is coiled loosely in thepiston chamber of the retardation tube 57 and it provides an operative connection between the conductor 84 and the upper carbon, so as to permit said carbon to descend with the piston head 68 with out interrupting the communication between.

the conductor 84, and said upper carbon. The current passes through the piston head 68 from the conductor 85 to the upper car bon by means which I will now describe The piston head 68 of the upper retardation device is constructed, to have a moderately tight frictional engagement "with the tube 67, so that it will at the same time be capable of a feed movement governed by and responsive to the adjustment of the valve 8l, for the purpose of controlling the gravity movement of the carbon A when it is released from the clutch. I prefer to make this piston head 68 from a solid block'of plumbago or graphite, and of the required dimensions to fit moderately tight within the tube 67, but to prevent the current from expanding, cracking or otherwise injuring connected with the binding post 59 this block, an air space is provided around the bolt 89. The bushings 87 are clamped to the end portions of the block by the plates or washers, 88. A bolt 89 passes through the block, and to the upper end of said bolt is attached an end portion of the conductor 85. The other end of the bolt has a ball-shaped head 90, which fits in the socket of a coupling member 91, said member being secured in the upper part of a tubular carbon holder 92, for the upper carbon This holder 92 is shown as having elastic jaws adapted to frictionally engage with the carbon A, for the purpose of holding it in place, and within the carbon holder is a washer 98. The head 90 and member 91 form a ball and socket connection for the carbon holder 92 with the piston head '88, thus permitting the operator to turn the carbon holder 92 freely without affecting the position of the piston. head within the retardation tube or, whereby the manipulation of the carbon holder by the attendant in removing and replacing a carbon will not disturb the cooperative position of the parts.

The are inclosing globe 25 is titted to a seat which is provided on plate 9%, said plate having insulating sleeves 95, arranged to on the tubes l2, 18, of the slidable frame, whereby the globe 25, as well as the lower carbon B, are supported wholly by the slidable frame.

The lamp should be provided with conductors and other accessories, such as are commonly supplied to ordinary arc lamps of this type to insure the operation of the parts.

As before indicated, the positive wire leading from a source of electrical supply, (not shown) is connected with the positive post 59, and similarly the negative Wire is The current on entering the lamp passes through the resistance coil 60, and thence through the magnet 62, which it energizes, whereby the armature 68 is drawn upwardly into the magnet @n the initial movement or this armature the clutch is operated for the pur pose of raising the 11 per carbon A. As the combined weight of t e armature, the clutch rod the dash-pot is removed from the slidable frame, the springs 16 act on the slidable frame, so as to impart an upward movement thereto, and to the lower carbon, B, The lower retardation device operates on the slidable frame to preclude any sudden and uneven movement of the lower carbon, while the springs act to impart movement to said frame and the lower carbon at speed required to keep the two carbons in contact. The springs 16 are so adjusted that they cause the slidable frame and the lower carbon to rise a prescribed distance, and when this distance has been traveled by said frame and the lower carbon, the upward movement of the frame and the carbon is arrested by pins 21 reaching the upper ends of slots 22 in frame rods lt will thus be seen that the lower carbon and the frame are lifted by the springs so that said lower carbon is raised simultaneously and in contact with the upper carbon During such elevation. of the two carbons, the clutch for the upper carbon is under the checking action of the dash pot, the carbon is under the checking'action 0]; the upper retardation device, and the slidable frame and lower carbon are under the checking" action of the lower retardation device, all the parts acting in harmony and insuring a steady upward movement to both can bone.

At the completion of the uplift of frame and the lower carbon under the ac oi the springs, upper carbon, A, with it the carbon holder 92 and the piston head are still drawn upward by the operation of the armature 63, and this continued upward movement Oil the upper carbon causes separation of the carbons to talre place, whereby the arc is established between the two carbons. @wing to consumption oi the carbons, the current wealrens in magnet 62, thus causing said magnet to ave less attractive force until clutch grip on the upper carbon A, whereupon the control of this carbon is transferred irom clutch to the retardation device, consisting of the tube 67 and piston head 68. W hen the retardation device is brought note service the piston head 68 descends slowly in the tube-6?, until the decreased distance between the two carbons causes the magnet 52 to regain its former power, and when magnet again becomes operative, the clot h is thrown into service so as to arrest a -ther descent of the carbons. llt will be understood that when the clutch releases grip on the upper carbon, the load or weight of said carbon is transferred from the on mature to the piston head and retard tion tube. Contact of the upper car with the lower carbon during the operation i the lamp is precluded by the retardati device, for the reason that a partial vacui. is produced in the chamber BWabovehead 68, and the external air exerts pressure against the under side of the piston ,us overcoming, when the strength of t as of the magnet is decreased, a sudden drop of the upper carbon into engagement mechanically/with the lower carbon,

From the foregoing it will be understood that in striking the arc, the two carbons, A, B, move simultaneously, the lower one, B, following the upper one and remaining in contact therewith so as to form. a closed path for the iiow of the current, but when said carbons are raised a certain distance, then the lower one is arrested while the up or one continues to move it wardl until the arc is struclr. ln the operation the lamp subsequent to the establishment of the arc, the lower carbon is held in its raised position by the springs acting on the lower ,slidable frame, while the upper carbon is controlled by the solenoid and clutch,'and by the upper retardation device. lhis control oi? the upper carbon precludes it from coming in mechanical contact with the lower carbon so long as the flow of current is uninterrupted through the lamp. When the carbons burn away, the strength of the current in the solenoid is decreased by the resistance of the are, which results inreleasing the clutch from carbon, A, whereupon the u or retar lotion device o erates to allow the gradual downward teed of said carbon until the current again flows with the required strength through the carbons and across the arc, and when the arc is restored the clutch is operated to lock the upper carbon, lln striking the arc accomplish my object by lreeping the carbons A, B, in their normal contacting positions a suiticient period of time'to allow the armature 63 to be drawn upwardly into a strong magnetic held, developed by the magnet 62, before separation of the two carbons can talre place,

In an arc lamp, the term dash pot is applied, ordinarily, to a device attached o or associated with the armature, core or plunger of a solenoid, the function of such a dash pot being to checlr and control the movement of the armature, core or plunger more especially upon the first admission of current to the lamp. The numeral 66 indisates the position of such a device in present lamp. lamp, the clutch being free from the upper carbon, the upward movement of armature 63 is first checked by the dash pottlu which operates to so control the upward movement of armature that ascends slowly. its the armature ascends, the clutch becomes operative, and bygripping the'carbon, car ries upward, the result of which action is to compress the air in the retardation tube above the piston head. 68 'This upward movement of the carbon compresses the air in the upper part of the retardation'device, and there is no sudden and powerful ins. pulse check, owing to the action or dash pot as, which operates on the carbon independently of the retardation device during the upward travel otthe carbon when current is first admitted. Atthis time, or dur-.

ing this operation, the upper carbon rests directly upon, and is supported by, the lower carbon, and the latter is in turn attached to the lower retardation tube and the sliolable trams l2, 13. When weight of the armature and the clutch is suddenly removed from tripping platform 9 When current enters the lull is a tendency for the lower carbon to be forced upward suddenly by the-expansive energy of 'coiled springs 16. This tendency is counteracted by lower retardation device- 4C3. Now, since the weight of the upper carbon alone is not sufiicient to hold the lower carbon down, it is raised slowly while resting upon the lower carbon. It is apparent that slidable frame 1213 and the springs coiiperating therewith constitute means for imparting motion to the lower and the upper carbons which are in contact with each other and upon the first admission of current to the lamp, such movement continuing until the lower carbon and the upper carbon shall have traveled a predetermined tance. Accordingly, it is apparent that the slidable frame bears a portion of the total weight of the armature, the clutch and the two carbons when said frame travels a certain distance, after which a part of the weight is transferred to the armature and the upper retardation tube. It is well understood by those familiar with are lamp construction that a certain amount of movement is allowed the armature before the clutch becomes operative, and in the present lamp, this movement of the armature is sufficient to relieve slidable frame 1213 of a part of the weight imposed thereon.-

lVere the retardation tube 43 entirely omitted, the slidable frame when relieved suddenly'of the weight of the armature would fly upward suddenly, such upward move ment being due to the action of springs 16,

but the retardation tube 43 acts through the carbons to hold the frame 1213 in check and imparts a steady movement thereto.

As showing that the upper dash pot 66 has no direct relation to or'connection with the retardation tube 43, we will assume that the solenoid has lifted the armature, thereby relieving the frame 1213 from the weight thereof. The piston of dash pot 66 binds, we will say, and, therefore, rises slowly.

The parts having been adjusted properly.

From the foregoing description it will be understood that the clutch responds quickly to fluctuations in the strength of the current and that it operates to engage and release the carbon A, whereas the upper retardation device is always in condition for use, for the purpose of controlling the descent of the upper carbon in a slow gradual manner when the clutch is free from said upper carbon. In the operation of feeding the carbon, the clutch or the piston head are always operative, and when the clutch lets go, the piston head checks and controls the descent of the carbon so as to make it ap proach the lower carbon with a gradual and slow feed movement. This results in the keeping the arc steady and uniform, and it secures a light which is characterized, not only by greater luminosity, but by a freedom from violet rays, the whole result being due to the fact that the full strength of the current is utilized in the production of the arc.

Changes in the form, size, proportion, and minor details of construction may be made without departing from the spirit of the invention or sacrificing any of the advantages thereof, and I,- therefore, reserve the right to make such alterations and modifications as fairly fall within the scope of my invention, as defined by the annexed claims.

Having thus described my invention, what I claim and desire to secure by Letters Patcut is 1. In an arc lamp, contacting upper and lower carbons, carriers therefor, means actuated by the flow of a current for raising the upper carbon, and separate means for simultaneously raising the lower carbon whilein contact with the, upper carbon, one of said carbons being moved relatively to the other carbon for a distance in excess of that through which the companion carbon is moved and at a time subsequent to the completion of the movement of said carbons while in contact with each other, whereby the arc is struck.

2. In an arc lamp, contacting upper and lower carbons, carriers therefor, means for guiding the lower carbon carrier in a rectilinear path, Ineansoperated by the flow" of simultaneously with, and at the speed of, the upper carbon, said current operated means for the upper carbon being adapted to move the upper carbon for a distance in excess of that through which the lower carbon is moved and to separate the upper carbon from the lower carbon at the completion of their simultaneous movement, whereby the arc is struck.

3. in an arc lamp, carbon carriers, upper and lower carbons adapted to contact with each other when no current is flowing, electrically-actuated mechanism for lifting the upper carbon and one of said carriers, and mechanical devices independent of said electrically-actuated devices for making the lower carbon rise simultaneously with the upward movement of the upper carbon, said electricallyoctuated mechanism being effec tive moving the upper carbon for a distance in excess of the distance through which the lower carbon is moved, thereby separat ing the carbons subsequent to the initial conjoint movement of the two carbons.

4t, an arc lamp, an upper carbon car rier, a lower carbon carrier, carbons in said carriers, means for directing each carbon carrier in a rectilinear path, means for lim iting the upward. movement of the lower carbon carrier, means operated bythe flow of an electric current for moving one of the carbons and its carrier, and mechanism for moving the other carbon and its carrier in a path corresponding to that of the first named carbon, said carbons moving while in contact with each other and for a predetermined distance on the initial flow of current through the lamp, one ofsaid devices being effective in moving one carbon for a distance in excess of that through which the other carbon is moved, thereby separating the two carbons subsequent to their conjoint move ment, for establishing the are.

5, in an arc lamp, contacting upper and lower carbons, carriers therefor, an electrically-controlled clutch for moving endwise the upper carbon, independent mechanism for moving the lower carbon while in contact with the first named carbon, thereby producing a closed path through the carbons for the initial flow of current through thelamp, and means for moving the upper car bon for a distance in excess of that through which the lower carbon is moved, thereby separating the carbons subsequent to their period of conjoint movement and striking the arc.

6. In an arc lamp, contacting carbons, carriers therefor, a clutch for lifting the upper carbon when currentis admitted to the lamp, an electro-magnet controllingsaid clutch, and mechanically operated devices acting on the lower carbon for causing it to follow the initial movement of the clutchcontrolled upper-carbon, and to remain in are-aces contact therewith during such following movement, said electro-magnet operating to move the upper carbon a cistance in excess of the distance through which the lower carbon is moved, thereby striking the are by separating the two carbons.

7. In an arc lamp, contacting carbons, carriers therefor, a clutch for raising the upper carbon when an electric current is admitted to a lamp, frame movable in rectilinear path, one of said carbon carriers being movable with said frame, and means acting on said frame for lifting the lower carbon and its carrier simultaneously with the elevation the upper carbon by said clutch, whereby said carbons remain in contact with each other during their initial upward movement, said clutch operating to lift the upper carbon a distance excess of the distance through which the lower carbon moves, v

8. in an. arc lamp, contacting carbons, carriers therefor, electrically-operated means for lifting the upper carbon when current is admitted to the lamp, a slidable frame supporting the carbon carrier for the lower carbon, said frame and the carbon carrier there for being adapted to be depressed by the weight of the upper carbon and a carrien therefor, and means for lifting the slidable frame and its'carbon carrier simultaneously with the upward movement of the upper carbon, whereby the two carbons are adapted to remain in mechanical engagement with each other and for a limited part of their upward movement, said electrically operated means being adapted to lift the upper carbon for a distance in excess of the distance through which the lower carbon is moved, wheerby the carbons areseparated and the arc is struck,

9. In an arc lamp, a lamp-frame, a foot plate pivotally connected to a part of said lamp frame and adapted for swinging adjustm'ent into andout of alinement with the position normally assumed by the carbons in the lamp, another frame slidable on the lamp frame, a carbon holder on the slidable frame, a retardation device carried by the foot-plate, and a separable connection between the retardation device and the slidable frame.

l0. lin an arc lamp, a lamp-frame, a movable member on said lamp frame, another slidable on the lamp-frame, a carbon carrier on the slidable frame, a retardation device on the movable member of the lamp-frame, and a separable connection between the retardation device and the slidable frame I ll. ltn an arc lamp, the combination of a lamp-frame, having a movable member connected with a stationary member of said frame, another frame slidable on the lampframe, a lower carbon carrier supported by said slidable frame, a piston head supported ill llll

lid

in a stationary position. on the movable member of the lamp-frame, a movable cylin der enveloping said piston head, and a separable connection between said cylinder and the slidable frame.

12. In an arc lamp, a lamp-frame having a swinging member, a retardation device carried by said swinging member, a slidable frame supported by the lamp frame, a lower carbon carrier on said slidable frame, and a ball and socket connection between the retardation device and a part of the slidable frame, said ball and socket connection having its members united detachably.

13. In an arc lamp, a slidable frame having a lower carbon carrier, a lamp frame, a retardation device supported by said lampframe and a separable connection between the retardation device and the slidable frame,

said separable connection comprising a rotative plug provided with a stud, and a thimble having a slot adapted for the reception of said stud on the rotative plug.

14. In an arc lamp, a lamp-frame having a depending casing, a threaded stem attached to said casing, a globe holder fitted to the casing, a nut screwed on the stem and engaging with the holder for clamping it to the casing, and a dog carried by the stem and cooperating with the nut for holding the latter in place.

15. In an arc lamp, a lamp-frame having tubular slotted members, a cross plate fitted slidably on the tubular members of said lamp-frame, spring actuated means slidable in the slots of the tubular frame members and connected with said cross plate for imparting slidable movement thereto, a carbon holder movable with the cross plate, and a current-controlled carbon holder adapted to support an upper carbon in alinement with a lower carbon which is to be supported in the holder on said cross plate.

16. In an arc lamp, a retardation tube, apiston-head therein, a carbon-carrier con nected to said piston-head, a closure attached to said tube above the piston-head therein,

said closure being provided with a single air port, a single check valve in coiiperative relation to said port in the closure and adapted to be seated and unseated by the movement of said piston-head in the re tardation tube, and an independent valve also in cooperative relation to the single port, said independent valve being adjustable relatively to the port for varying the effective area of said port.

17 In an arc lamp, a retardation tube, a piston-head therein, a carbon-carrier connected to said piston-head, a closure attached to said tube above the piston-head therein, said closure being provided with a single air port, a single check valve in cooperative relation to said port in the closure and adapted to be seated and unseated by the movement of said piston-head in the retardation tube, a plug adjustable in said tube relative to the closure, and a regulating valve carried by said plug and disposed in coiiperative relation to the aforesaid port for varying the eflective area thereof, said check valve and the regulating valve coiiperating with the respective sides of the closure and the port therein.

18. In an arc lamp, a top plate, a retardation tube for an upper carbon, and a swiveled connection between said retardation tube and the top-plate, whereby the tube is suspended from the plate and is free to have rotating adjustment relative thereto.

19. In an arc lamp, a top plate, a retardation tube for an upper carbon, a closure at-- tached to said tube and lying below the topplate, and a ball and socket connection between the top plate and said closure, whereby the tube is suspended from the plate and is free to have rotating adjustment relative thereto.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FREDERICK W. GORE.

Witnesses:

H. T. BERNHARD, James H. Gum-1N. 

